The History of Writing Reflects the Effects of Education on Discourse Structure: Implications for Literacy, Orality, Psychosis and the Axial Age

Speech as a Graph: Developmental Perspectives on the Organization of Spoken Language

Language has been used as a privileged window to investigate mental processes. More recently, descriptions of psychopathological symptoms have been analyzed with the help of natural language processing tools. An example is the study of speech organization using graph theoretical approaches that began approximately 10 years ago. After its application in different areas, there is a need to better characterize what aspects can be associated with typical and atypical behavior throughout the lifespan, given the variables related to aging as well as biological and social contexts. The precise quantification of mental processes assessed through language may allow us to disentangle biological/social markers by looking at naturalistic protocols in different contexts. In this review, we discuss 10 years of studies in which word recurrence graphs were adopted to characterize the chain of thoughts expressed by individuals while producing discourse. Initially developed to understand formal thought disorder in the context of psychotic syndromes, this line of research has been expanded to understand the atypical development in different stages of psychosis and differential diagnosis (such as dementia) as well as the typical development of thought organization in school-age children/teenagers in naturalistic and school-based protocols. We comment on the effects of environmental factors, such as education and reading habits (in monolingual and bilingual contexts), in clinical and nonclinical populations at different developmental stages (from childhood to older adulthood, considering aging effects on cognition). Looking toward the future, there is an opportunity to use word recurrence graphs to address complex questions that consider biological/social factors within a developmental perspective in typical and atypical contexts.

Just a mark: Diacritic function does not play a role in the early stages of visual word recognition

A very common feature in most writing systems is the presence of diacritics: distinguishing marks that are added for various linguistic reasons. Most models of reading, however, have not yet captured the nature of these marks. Recent priming experiments in several languages have attempted to resolve how diacritical letters are represented in the visual word recognition system. Since the function and appearance of diacritics can change from one language to the other, it is hard to interpret the accumulated evidence. With this in mind, we conducted two masked priming lexical decision experiments in Hungarian, a transparent orthography with a wide use of diacritic vowels that allows for clear-cut manipulations. In the two experiments, we manipulated the presence or absence of the same diacritic (i.e., the acute accent) on two specific sets of letters that behave differently. In Experiment 1, the manipulation changed only the length of vowels, whereas in Experiment 2, it also changed the quality (e.g., a↝/ɒ/ vs. á↝/aː/). In both experiments, we found that primes with an omitted diacritic work just as good as the identity primes (nema→NÉMA = néma→NÉMA [mute]), whereas the addition of a diacritic comes with a cost (mése→MESE > mese→MESE [tale]). This asymmetry favors a purely perceptual account of the very early stages of word recognition, making it blind to the function of diacritics. We suggest that the linguistic functions of diacritics originate at later processing stages.

Reading and writing habits compensate for aging effects in speech connectedness

We investigate the association of short- and long-range recurrences (speech connectedness) with age, education, and reading and writing habits (RWH) in typical aging using an oral narrative production task. Oral narrative transcriptions were represented as word-graphs to measure short- and long-range recurrences. Speech connectedness was explained by the combination of age, education, and RWH, and the strength of RWH's coefficient reflects the aging effect.

Nonsemantic word graphs of texts spanning ∼ 4500 years, including pre-literate Amerindian oral narratives

Non-semantic word graphs obtained from oral reports are useful to describe cognitive decline in psychiatric conditions such as Schizophrenia, as well as education-related gains in discourse structure during typical development. Here we provide non-semantic word graph attributes of texts spanning approximately 4500 years of history, and pre-literate Amerindian oral narratives. The dataset assessed comprises 707 literary texts representative of 9 different Afro-Eurasian traditions (Syro-Mesopotamian, Egyptian, Hinduist, Persian, Judeo-Christian, Greek-Roman, Medieval, Modern and Contemporary), and Amerindian narratives (N = 39) obtained from a single ethnic group from South America (Kalapalo, N = 18), or from a mixed ethnic group from South, Central and North America (non-Kalapalo, N = 21). The present article provides detailed information about each text or narrative, including measurements of four graph attributes of interest: number of nodes (lexical diversity), repeated edges (short-range recurrence), largest strongly connected component (long-range recurrence), and average shortest path (graph length).